A method of this genus is known from DDR Patent 212 573. This patent describes exposing metal surfaces to a plasma that contains a silane. An adhesion-promoting coat accordingly forms on the surface and provides a secure but resilient attachment between the surface and a plastic applied thereto. Experience demonstrates, however, that this method does not always ensure adequate strength. The method also requires a strictly metal surface as a base, and existing structures of both metal and plastic whereby the plastic is chipped for example cannot be satisfactorily repaired. Applying known adhesion-promoting coats of this type to a metal framework by flame pyrolysis is also known. This approach heats the metal up very high, which can lead to undesired thermal failure. Furthermore, flame pyrolysis cannot be employed to repair surfaces that are at least partly of plastic.
Cleaning metal surfaces with a plasma is known from U.S. Pat. No. 5,188,800. German Patent 3 316 742 discloses both a method of cleaning metal surfaces with plasma and method of coating them with titanium.
The object of the present invention is an improved method of treatment with plasma in accordance with the prior art hereintofore discussed wherein the surface of the work can be provided with a reliably adherent coat that contains silane.